Did the conversion kit come with new springs as well? If the gun is set up to handle 10mm recoil, does the .40 have enough "power" to fully cycle the gun with the 10mm springs in place?
Wait for a better response, but from what I've heard you also need a new extractor possibly for the .40??
The factory-loaded .40 S&W JHP that I use gets similar or better performance than that!
Perhaps you can explain in detail "failure to feed".
LWD barrels lock up tighter than OEM and that might be your problem. I had a problem where the slide lacked ~1/16-3/32" from full lock up and it took only thumb pressure to get full lock up. I stoned/polished the breech face to make sure the face was smooth and not causing additional friction then gradually removed the sharp edge on forward barrel lug. After a little work the slide began to closed properly. You might want to slowly close the slide and watch the caming action to see if there is any binding.
My 10-40 LWD barrel now works fine and I've always used the stock G20 recoil spring so the spring was never an issue.
I am REALLY surprised that oil could make that big of a difference though, I have run the Glock barrel dry and never had an issue.
Yeah, it needs to have at least 200 more failure free rounds through it before I consider it for anything other that practice and recreationManco said:Hmmm...while proper lubrication is highly advisable for maximum reliability and minimal wear, Glocks should be able to function reasonably well when dry. If you're not going to depend on the weapon for self-defense in this configuration (i.e. with the conversion barrel installed) and are satisfied with the results you're getting now, then I guess that's OK, but something still seems wrong to me.
And given that all the full size Glocks use the same weight spring, I doubt it's a spring issue.
Yeah I thought about saying something similar, but telling someone whose handyman skills you don't know to make irreversible changes to something they may opt to send back is not my first suggestion.I had the same issue. I mic'd out the outside dimensions of the chamber area and found it to be about four thousands larger than the stock barrel. I took a wetstone and removed equal amounts of material from both sides. After that no problem. I didnt change any springs either. YMMV